Pump



April 22, 1958 F. SCHMIDT ETAL 2,831,436

PUMP

4 Sheets-Sheet 1 Filed Aug. 11, 1953 Ellie Say/vim" W1 p 2, 1958 F. SCHMIDT ETAL 2,831,436

PUMP

Filed Aug. 11, 1953 4 Sheets-Sheet 2 Fig.

NVENTOR.

Farr; su/ nio'r mm Em'c/l Sc/s MlbT P 2, 1958 F. SCHMlD'l ETAL 2,831,436

PUMP Filed Aug. 11, 1953 4 Sheets-Sheet 3 26 25 27 Fig-9 Y 44 4? f' F1942 INVEN TOR. FRITZ Selim/p1 190 0 April 22, 1958 F. SCHMIDT ETAL 2,831,436

' PUMP Filed Aug. 11, 1953 4 Sheets-Sheet 4 Fig.44

INVENTOR;

FRITZ. ScHMioT nun ERiC/i Sci/MID PUMP Fritz Schmidt and Erich Schmidt, Vienna-Britain, Austria, assignors to Garvenswerke Maschinen, Pompom und Waageufabrik W. Garvens, Vienna, Austria Application August 11, 1953, Serial No. 373,556-

Claims priority, application Austria August 19, 1952 10 Claims. (Cl. 103-127) This invention relates to pumps, in the meaning of that term including compressors.

Pumps and compressors are known which comprise, two members having profiled side facesfacing each other, onwhich side faces there are provided spiral flutes which engage each other along a parting line which has suction and pressure zones on either side thereof. Along that parting line the two members are sealed against each other so that that line can also be called a sealing line. The pumping or compressing action is obtained by the formation of crescent shaped spaces during rotation of said members, said spaces extending through almost 360 deg. and terminating in points within the spiral flutes, which spaces during the rotation of the profiled members are displaced outwardly or inwardly depending on the sense of rotation or direction of conveyance and thereby become wider or narrower, respectively.

In knownmachines of that type one of the members is stationary whereas the second is rotatably mounted on a pin forming an oblique continuation of and rotated by the drive shaft. In that construction strong centrifugal forces, which cannot be compensated, result from the relative motion between the two members during the high driving shaft speeds necessary.

The present invention eliminates that drawback of machines of the type described by also rotatingly driving the one member, but also providing for the second member, which is rotatably mounted on an axis slightly inclined to the axis of the first member, to be taken along by the rotation of the first member, the parting orsealing line extending outwardly, i. e., the points where the several spiral flutes are sealed, remaining substantially in one plane or in one surface, which is determined by the axes of the disks.

Additional features of the invention and advantageous constructions thereof will be apparent from the embodiments of the invention described hereinafter with reference to the drawing.

Fig. 1 is a sectional view of a pump, taken along line I--I of Fig. 2.

Fig. 2 is a sectional view taken along line Ill-11 of Fig. 1.

Fig. 3 shows a central sectional view of one of the two members of the pump of Figs. 1 and 2.

Fig. 4 is an end view of the helical turns on the sealing face of such pump, with a multiple spiral.

Fig. 5 is an end view of the helical turns of a singlespiral pump of that type.

Figs. 6 and 7 show two further forms of the profile of the pump members.

Figs. 8 to 11 show further different cross-sectional forms of helical flute profiles.

Fig. 12 is a meridian-sectional view of another example of construction of the spiral pump.

Fig. 13 is a sectional view of an. example of a construction of the pump, in which the drive is. transmitted by gears.

atent ice Fig. 14 is asectional view ofa further example of a construction of the pump illustrating some constructional details. I

According to Figsal to 3 a disk 1 is fixed on a shaft 2, e. g. a shaft stub ofa motor, and has on its end face a profile 3 of spiral flute turns. The disk 5 which is rotatably mounted in abearing. 6has spiral turns 4 fitting the spiral turns of disk 1 which consist as usual of a rib and an adjoining groove each: extending more than 360.

When the disk 1 is rotated, it drivesthe disk 5 through spiral turns 3 and spiral turns 4. The axes of rotation because due to the lead of the spiral their tangents are not exactly. at right angles to the appertaining. radius.

Due to the inclination of the twoaxes, the, spiral turns 3 and spiral. turns. 4 fit each other to make a liquid or gas seal along ai radial parting line approximately between; points 8v and' 9, where they completely fill the flutes and are thus in closed mesh. On the opposite side cavities 10- are formed within thev spiral flutes. The extremeties of the spiral flutes 3 are spaced from the bottom of the spiral groovebetween the. turns. while the extremeties of turns 4 are, spaced from the bottom of the groovebetween turns 3.. Thespherical surfaces on the sides are still in contact, however, the spiral turns 3 and 4 thus being in open mesh.

When the disks rotatein v the directionv of arrow z Fig. 2), e. g, air entersjthe. inlet totthei groove between the turns 3 and 4 in the-direction. of arrow 11 into the outermost spiral and is conveyed from there inwardly in the direction of. the, spiral. fluteturns. When the end of the outermost spiral turn reaches the point 9, the turns of spiral flute 3 sealingly engage the turns of the spiral flute 4 so that the entrance of air is prevented in that position.

Thus a, crescent-shaped space filled with air or another medium to-be conveyed is formed within each spiral turn by the parting or sealing line, which remains in place, and by the side faces of the spiral flutes, which are in sealing engagement with each other. Due to the rotation of the disks and the sealalong the parting line remaining in place, the air or gas content of all spiral cavities is urged. inwardly toward the outlet opening 13. Since each succeeding crescent-shaped cavity is of smaller cubic content due to the spiral shape and the reduction in the depth of the flutes, the air or another medium is compressed at the same time. The pressure obtainable within the spiral turnsdepends: on. their number and inclination, i. e. on the difference between the cubic content of the outermost and innermost spiral turns. For instance, when theair discharged. by high-pressure pumps is collected in an air receiver, the pressure therein may be as high as desired, the pressure in the. central turn of the spiral being, a function of the pressure in the outermost turn of the spiral and of the difference in volume between the outermost and innermost turns of the spiral.

Fig. 3 shows a disk (1 or 5) constructed as shown in Fig. 1, the line 1515 being at right angles to the axis of rotation of the diskand intersecting the axisof rotation at the center; of the spiral. The line 7-16, called the profilecente r line, deviates downwardly by half the angle of inclination between, the two axes of rotation. The lines,7--17'and 7-18 are calledtheprofile head line and profile base line, respectively.

- Patented: Apr. 22, 1958 In the form of Fig. 1 the profile center lines, profile head lines and profile base lines of both disks have the same inclinations or angles. The cavities are sealed at points 10' by a slight mutual overlapping contact of thespherical side faces 3' and 4', which are also curved in accordance with the spiral shape, of course. Due to the spherical shape of the side faces 3' and 4' the spirals cannot be pushed one into the other. For this reason the construction requires at least one disk'to consist entirely or partly, e. g. at the sealing faces, of elastic material.

When both disks 1 and 5 are made from surliciently elastic and wear-resistant material, e. g. the material known under the trademark Akulon, it may be sufficient to form the solid walls 3 and 4' of-the spirals parallel to the disk axis. Obviously that form is suitable only for spiral flutes of small depth and for small conveying capacities.

The conveying capacity can be increased by an increase in the size of the disks 1 and 5, the lead of the spirals, the angle of inclination of the axes andof the number of spirals. In the example of Fig. 4 two spirals 19 and 21 and two grooves and 22, are shown, each extending approximately 630", with separate outlets at the periphery. Two such disks together will form four series of cavities. That form is most suitable for the conveyance of liquids.

As contrasted therewith Fig. 5 shows a disk with a single spiral and a single groove, each extending 1260". For reasons of manufacture the spiral flute turn is subdivided bymeans of an intermediate rib of lower height than the spiral flute turns. That subdivision may be employed to increase or reduce the volume of a spiral flute turn. For higher pressure the cubic capacity of the inner spiral flute turns will be reduced relative to the outer ones by giving the subdividing rib a larger cross-sectional area. For low pressure the capacity of each cresent space is to be kept large; for the conveyance of liquids it is to be kept equal for each angular position of rotation, respectively.

The examples of Figs. 6 and 7 show disks having no continuous spiral turns but concentric flute turns 23 connected by channels 24. The resulting side walls of channels 24 serve for the driving engagement between the two disks 1 and 5. Here too the conveying channels convey continuously from the center outwardly or from the outside inwardly.

Fig. 8 shows a profile for a disk construction according to Fig. 5. In that construction elevations of different height, called steps 25, are provided within the spiral flute turns. The several spiral flute turns are closed by the spherical side walls 26 curved about the center 7 of the spiral. The profile head line does not pass through the spiral center 7 but the points 27 lie on a plane surface which extend at right angles to the axis of rotation of the disk 1 or 5. The bottom portions 28 of the subdividing steps lie on a surface parallel to that plane.

The profile base line intersects the axis of the disk at a point which is the same distance apart from the spiral center (intersection of the inclined axis) as is the intersection of the head profile line or plane with said axis. That profile facilitates the manufacture of the spirals.

In the construction according to Fig. 9 the profile base lines 30 of the single spiral flute turn lie on a cone and pass through the spiral center 7. The connecting portions 31 are of spiral or approximately spherical shape. The profile head line passes through the spiral center. The side faces of the spiral flute turns are spherical surfaces, the center of which is at the spiral center. That form can be manufactured by means of face boring equipment.

The construction according to Fig. 10 is based on a logarithmic spiral. All surfaces 33 of the profile are parallel conical surfaces, the surfaces 34 are spherical. The spiral flute turns decreasing according to the logarithmic spiral, this construction enables a high vacuum or maximum compression to be achieved. The profile headline and profile base line extend to the spiral center. The manufacture can be effected on relieving lathes with duplicating attachment.

The construction according to Fig. 11 is suitable particularly for larger pumps or compressors. The spherical scaling surfaces 35 of the spiral have their center at the spiral center 7 and the surfaces 36 are those of cones of different taper. The-head and base points 37 and 38 lie on Archimedian spirals.

Fig. 12 shows a spiral pump particularly for water, oils and gases. in that construction e. g., the medium to be conveyed is sucked through the inlet bore 40 and leaves the pump through an outlet in the direction of arrow 41.

The hollow-conical form of the member 43 also serves for centering. For instance, the disk 42 or 43 may be made at least in part of plastics, compression-molding-material, or hard rubber. That construction is suitable particularly for highest speeds.

The angle 47 at the center of the profile cone, measured on the side remote from the sealing surface, is 233 deg. for disk 43. The angle 48 at the center of the spiral cone on disk 42 is 121 deg. The total of the two component cone angles is 233 deg-H21 deg.=354 deg. The balance of 6 deg. to give 360 deg. is the angle of opening. That angle of opening is the basic magnitude for the calculation of the conveying capacity of spiral pumps.

Drivers, gear teeth, particularly bevel gears, for intercoupling the two members may be arranged on disks 1 and 5 or on disks all and 4-3.

Such an embodiment is shown in Fig. 13.

Here bevel gear teeth 51, 52 are provided on the mutually facing surfaces of the two pump disks and in most perfect mesh adjacent to the sealing line. When spur gear teeth (indicated with dash-and-do-t lines) are arranged at the periphery of both pump disks, a pinion 55 is arranged at one point of each disk, e. g. at 53 and 54, to mesh with both spur gear toothings. Then both pump disks may be driven through the shaft 56.

Fig. 14 illustrates a pump according to the invention in greater detail. 1 and 5 denote the two disks, the disk 1 being rotated by means of its shaft 62 and a motor (not shown) in a bearing bushing 63. A stutfing box including the gland and a packing 64 prevent entrance of air. The axis of the second disk 5 has a central bore 13 and the disk is provided with a plurality of centrally arranged channels 68 and with a spherical calotte 80 bearing on a brass bushing in the other disk, the axes of the disks intersecting at 7, The axis of disk 5 is surrounded by a bearing bushing 71 and both disks are enclosed in a casing 60 having a cover 61 secured to the said casing by nuts 81. The cover 61 has an entrance or suction opening 67 for the medium to be pumped and forms the suction chamber 67'. The casing 60 is provided with an outlet or opening for the compressed medium and forms a pressure chamber 66. The casing and its cover are sealed by a suitable packing 82. Between the surfaces within the spiral flute turns are inserted suitable tightening media 75, such as rubber or plastics, e. g. the material known by its commercial name Simmerit.

If shaft 62 is rotated clockwise and the entrance opening 67 is submerged, the medium fills the chamber 67 and passes through the hollow bore 13 and channels 68 into the chamber 69. When the disks are rotated the medium is thrown by centrifugal force outwardly into the chamber 69, from where it is passed into the spiral flutes and discharged under pressure into the high pressure chamber 66, from which it leaves the pump by the outlet opening 70.

When the disks are stopped, the level of a liquid medium will fall to the lower edge of the entrance opening and the chambers 67', 69 and 66 remain partly filled. On starting the pump again, the liquid medium will be transferred from chamber 67 into the high pressure chamber 66 and creates a vacuum in 67', thereby sucking air in at the beginning and later drawing liquid medium out of a suction conduit connected to the entrance opening.

assnsse What we claim is:

l. A pump which comprises, in combination,:two members having mutually facing end faces having spiral flute turns extending more than 360 thereon and defining grooves between them, said members having longitudinal central axes of rotation which are inclined to each other and which extend through the centers of the spirals, the sides of all of said spiral flute turns of one of said members being in sealing engagement with the sides of the spiral flute turns of the other of said members so that said flute turns are in closed mesh along a parting line extending outwardly from the center of the spiral, the peripheries of said end faces engaging each other at the radially outer end of said parting line and diverging therefrom to a diametrically opposed point of said end faces, where said flutes are in open mesh, the ends of said grooves forming an inlet and an outlet from said pump, and means for rotating at least one of said members about its axis, the other of said members being mounted for rotation about its axis, said members being in constant bers having mutually facing end faces having spiral flute turns extending more than 360 thereon and defining grooves between them, bottoms between said spiral flute turns which lie on a convex conoidal surface, spiral rib turns on said bottoms between radially adjacent spiral flute turns the tops of which ribs lie on a concave conoidal surface, said members having longitudinal central axes of rotation which are inclined to each other and which extend through the centers of the spirals, the sides of all of said spiral flute turns of one of said members being in sealing engagement with the sides of the spiral flute turns of the other of said members so that said flute turns are in closed mesh along a parting line extending outwardly from the center of the spiral, the peripheries of said end faces engaging each other at the radially outer end of said parting line and diverging therefrom to a diametrically opposed point of said end faces, where said flutes are in open mesh, the ends of said grooves forming an inlet and an outlet from said pump, and means for rotating one of said members about its axis, the other of said members being mounted for rotation about its axis, said members being in constant driving engagement with each other for a rotation of each of said members on its axis during which the parting ,line remains stationary.

3. A pump which comprises, in combination, two members having mutually facing end faces having spiral flute turns extending more than 360 thereon and defining grooves between them, said members having longitudinal central axes of rotation which are inclined to each other and which extend through the centers of the spirals, the sides of all of said spiral flute turns of one of said members being in sealing engagement with the sides of the spiral flute turns of the other of said members so that said flute turns are in closed mesh along a parting line extending outwardly from the center of the spiral, the peripheries of said end faces engaging each other at the radially outer end of said parting line and diverging therefrom to a diametrically opposed point of said end faces, where said flutes are in open mesh, the ends of said grooves forming an inlet and an outlet from said pump, and means for rotating one of said members about its axis, the other of said members being mounted for rota tion about its axis, said members being in constant driving engagement with each other for a rotation of each of said members on its axis during which the parting line remains stationary, said flute turns on each member having substantially spherically curved side faces, the center of curvature of which is on the axis of rotation of that member, whereby said flute turns are kept in sealing engagement with each other during rotation of said members.

4. A pump which comprises, in combination, two members having mutually facing end faces having spiral flute turns extending more than 360 thereon and defining grooves between them, said members having longitudinal central axes of rotation which are inclined to each other and which extend through the centers of the spirals, the sides of all of said spiral flute turns of one of said members being in sealing engagement with the sides of the spiral flute turns of the other of said members so that said flute turns are in closed mesh along a parting line extending outwardly from the center of the spiral, the peripheries of said end faces engaging each other at the radially outer end of said parting line and diverging therefrom to a diametrically opposed point of said end faces, where said flutes are in open mesh, the ends of said grooves forming an inlet and an outlet from said pump, and means for rotating one of said members about its axis, the other of said members being mounted for rotation about its axis, said members being in constant driving engagement with each other for a rotation of each of said members on its axis during which the parting line remains stationary, said flute turns on each member having substantially spherically curved side faces, the center of curvature of which is on the axis of rotation of that member, and said flute turns being at least partly of resilient material, whereby said flute turns are kept in sealing engagement with each other during rotation of said members.

v5. A pump which comprises, in combination, two members having mutually facing end faces having spiral flute turns extending more than 360 thereon and defining a plurality of spiral grooves thereon each having a peripheral suction opening and a central discharge opening, a plurality of spiral rib turns thereon one between each of said flute turns, said members having longitudinal central axes of rotation which are inclined to each other and which extend through the centers of the spirals, the sides of all of said spiral flute turns of one of said members being in sealing engagement with the sides of the spiral flute turns of the other of said members so that said flute turns are in closed mesh along a parting line extending outwardly from the center of the spiral, the peripheries of said end faces engaging each other at the radially outer end of said parting line and diverging therefrom to a diametrically opposed point of said end faces, where said flutes are in open mesh, the ends of said grooves forming an inlet and an outlet from said pump, and means for rotating at least one of said members about its axis, the other of said members being mounted for rotation about its axis, said members being in constant driving engagement with each other for a rotation of each of said members on its axis during which the parting line remains stationary.

6. A pump which comprises, in combination, two members having mutually facing end faces having spiral flute turns extending more than 360 thereon and defining grooves between them, each consisting of a circular flute portion and a connecting flute portion connected to the next adjacent flute turn in the direction of the center of said members, a plurality of spiral rib turns one between each of said flute turns, said members having longitudinal central axes of rotation which are inclined to each other and which extend through the centers of the spirals, the sides of all of said spiral flute turns of one of said members being in sealing engagement with the sides of the spiral flute turns of the other of said members so that said flute turns are in closed mesh along a parting line extending outwardly from the center of the spiral, the peripheries of said end faces engaging each other at the radially outer end of said parting line and diverging therefrom to a diametrically opposed point of said end faces, where said flutes are in open mesh, the ends of said grooves forming an inlet and an outlet from said pump, and means for rotating one of said members about its axis, the other of said members being mounted for rotation about its axis, said members being in constant driving engagement with each other for a rotation of each of said members on its axis during which the parting line remains stationary.

7. A pump which comprises, in combination, two members having mutually facing end faces having spiral flute turns extending more than 360 thereon and defining grooves between them, spiral rib turns between said spiral flute turns, said members having longitudinal central axes of rotation which are inclined to each other and which extend through the centers of the spirals, the sides of all of said spiral flute turns of one of said members being in sealing engagement with the sides of the spiral flute turns of the other of said members so that said flute turns are in closed mesh along a parting line extending outwardly from the center of the spiral, the peripheries of said end faces engaging each other at the radially outer end of said parting line and diverging therefrom to a diametrically opposed point of said end faces, where said flutes are in open mesh, the ends of said grooves forming an inlet and an outlet from said pump, the height of said spiral flutes and spiral ribs being such that imaginary surfaces bisecting the height of the rib turns and the flute turns defined cones having coinciding apexes and having different tapers, to leave an angle of opening between said members, and

means for rotating at least one of said members about its axis, the other of said members being mounted for rotation about its axis, said members being in constant driving engagement with each other for a rotation of each of said members on its axis during which the parting line remains stationary.

8. A pump which comprises, in combination, two memoers having mutually facing end faces having spiral flute turns extending more than 360 thereon and defining grooves between them, said members having longitudinal central axes of rotation which are inclined to each other and which extend through the centers of the spirals, the sides of all of said spiral flute turns of one of said members being in sealing engagement with the sides of the spiral flute turns of the other of said members so that said flute turns are in closed mesh along a parting line extending outwardly from the center of the spiral, the peripheries of said end faces engaging each other at the radially outer end of said parting line and diverging therefrom to a diametrically opposed point of said end faces, where said flutes are in open mesh, the ends of said grooves forming an inlet and an outlet from said pump, means for rotating one of said members about its axis, the other of said members being mounted for rotation about its axis, and meshing driver means in driving engagement with the periphery of each of said members for maintaining said members in constant driving engagement with each other for a rotation of each of said members on its axis during which the parting line remains stationary. 9. A pump which comprises, in combination, two members having mutually facing end faces having spiral flute turns extending more than 360 thereon and defining grooves between them, said members having longitudinal central axes of rotation which are inclined to each faces, where said flutes are in open mesh, the ends of said grooves forming an inlet and an outlet from said pump, means for rotating one of said members about its axis, the other of said members being mounted for rotation about its axis, and meshing tooth means in driving engagement with the periphery of each of said members for maintaining said members in constant driving engagement with each other for a rotation of each of said members on its axis during which the parting line remains stationary.

10. A pump which comprises, in combination, two members having mutually facing end faces having spiral flute turns extending more than 360 thereon and defining grooves between them, at least one of said members consisting entirely of resilient material, said members having longitudinal central axes of rotation which are inclined to each other and which extend through the centers of the spirals, the sides of all of said spiral flute turns of one of said members being in sealing engagement with the sides of the spiral flute turns of the other of said members so that said flute turns are in closed mesh along a parting line extending outwardly from the center of the spiral, the peripheries of said end faces engaging each other at the radially outer end of said parting line and diverging therefrom to a diametrically opposed point of said end faces, where said flutes are in open mesh, the ends of said grooves forming an inlet and an outlet from said pump, and means for rotating at least one of said members about its axis, the other of said members being mounted for rotation about its axis, said members being in constant driving engagement with each other for a rotation of each of said members on its axis during which the parting line remains stationary.

References Cited in the file of this patent UNITED STATES PATENTS 

